Mailspring
Mailspring is a free, open-source email and calendar app for Windows, macOS and Linux. A beautiful, fast and fully open source mail client for Mac, Windows and Linux. It has 17,956 GitHub stars and is released under the GPL-3.0 license, and people use it instead of Microsoft Outlook.
github.com/Foundry376/Mailspring (opens in a new tab)
Data as of from the GitHub API; description from the project's repository. Report an error
About Mailspring
Mailspring is a new version of Nylas Mail maintained by one of the original authors. It's faster, leaner, and shipping today! It replaces the JavaScript sync code in Nylas Mail with a new C++ sync engine based on Mailcore2. It uses roughly half the RAM and CPU of Nylas Mail and idles with almost zero "CPU Wakes", which translates to great battery life. It also has an entirely revamped composer and other great new features.
Replaces
Commercial software people commonly use Mailspring instead of.
- Microsoft Outlook
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Is Mailspring free and open source?
Yes. Mailspring's source code is public on GitHub under the GPL-3.0 license, which is OSI-approved or FSF-free, so you can use, copy and change it for free.
How do I install Mailspring?
Download the installer for Windows, macOS and Linux from its GitHub Releases page (latest: 1.26.2) or the project website.
Can Mailspring replace Microsoft Outlook?
Mailspring is commonly used as a free alternative to Microsoft Outlook. Features differ, so check that it opens the file formats and covers the workflows you rely on before switching.